Back to IGS | FAQ | Contact

Does anyone know if this is agate or Jasper?

It kinda looks like opalized petrified wood. But can’t be sure.

1 Like

I can send you a better pic , sorry for long wait. Thank u for responding

That was my first thought as well, petrified wood with opalization or silica replacement. It certainly does not look like an agate at any rate. If it is harder than a 5.5 Mohs, then probably call it Jasper. The problem is that in photo form it is hard to relay all the data that an experienced mineralogy expert uses (sheen, fracture, weight etc) to evaluate.

Best to ask someone locally, for best results.

Yes I also thought opalised wood on first pic but second pic leads me to think it could be chalcedony
thanks.

1 Like

Thanks for the reply, there is a lot of many different colors involved in this specimen, from white, green, blue, dark blue, purple, a reddish aswell. Many tiny silver specs that glitter when light hits it. When I found it I packed it all day cutting logs intell I met log skidder at the end. It weighed 58.5 lbs before cutt in half. Thanks again. Your information and thought into it really helps with research. It’s little brother is more colorful and smaller, in my opinion more unique in color aspect. If you would like I can send a few photos, your way to hear your opinion. Agian thanks

Where did you find this, looks like chalcedony agate. Found some in Nevada. Let me know when you find out

I found the stone in Idaho on some privite ground we logged near Oregon boarder Jordan valley. Owners said keep what you find , so I dug it out when I seen it and it’s little brother that I have here aswell. It located at top of cow creek then north west of silver city. I think it’s a cool stone, it’s baby brother is unique aswell , has many colors and took alot of time to cut in half. Couple blades aswell. I will send you pic .




This is it’s baby brother, about 100 yards or so away.

The discussion above is good, but it is time to zero in on the ID by some testing. Chip off a few samples and run an SG (Specific Gravity Measurement) on them. Agates and Jasper are Chalcedony so their nominal SG will be 2.60 and steady while taking the wet weight. If opal, then the nominal SG will be 2.15 (less dense) AND the wet weight will not be steady in the SG apparatus. If your scale is sensitive enough (mine goes out 5 decimal places to the right of the decimal or 1 one-hundred thousandth of a gram) the wet weight of the specimen will continue to increase in weight as part of the chemical formulary of opal contains a (n) number of H2O molecules … the specimen absorbs water molecules while being measured, thus getting heavier. Seeing the specimen get heavier during the wet weight SG measurement is a sure indicator that you have opal. I have seen this time and time again when opals come in for analysis in my lab. I hope this helps you make the final positive ID. :smiley:

Thanks for insight and knowledge , I will do my best and send results your way. Thank agian and I’m sure I will have some questions in process and if I do I will let you know

So I did a sc analysis on the small stone, it’s results came to 2.4



I wasent able to get to the bigger stone, I will proceed with that tonight. Thanks

Here are some better pics of the small stone




I have an agatized root ball that looks similar to your pictures, though mine is lighter in color, and it is made up of petrified wood, opal and agate. The yellow coloration in yours could be a type of opal, though not of the high end